咪唑基离子液体IL-MPEG1000的合成及其对PLA性能的影响

Synthesis of the imidazolium ionic liquid IL-MPEG1000 and its influences on the properties of PLA

本研究合成了一种含聚乙二醇单甲醚(MPEG1000)结构的咪唑基离子液体(IL-MPEG1000),并采用核磁共振(1 H NMR)对其进行了结构确认。通过熔融共混法制备系列含IL-MPEG1000的聚乳酸(PLA)试样,应用差示扫描量热法(DSC)、热失重测试(TG)、扫描电子显微镜(SEM)研究了IL-MPEG1000对PLA性能的影响。DSC结果表明,IL-MPEG1000促使PLA玻璃化转变温度的降低,并导致PLA试样在升温过程中出现了明显的结晶峰与熔融双峰,说明IL-MPEG1000提高了PLA链段的运动能力。SEM观察到含IL-MPEG1000的PLA试样出现韧断现象,表明IL-MPEG1000起着增韧作用。然而,TG分析表明IL-MPEG1000的加入降低了PLA的热稳定性。

Imidazolium ionic liquid IL-MPEG1000 was synthesized, and its structure was confirmed by 1H-NMR. And then, the series of PLA samples contained different amount of IL-MPEG1000 were prepared by melt-blending. The effects of IL-MPEG1000 on the properties of PLA were investigated by DSC,TG and SEM. The PLA samples contained IL-MPEG1000 showed obvious crystallization peaks and double melting peaks with increasing of temperature as shown in DSC curves, and the Tg of PLA was effectively decreased, which indicated that the mobility of PLA chain segments was increased due to the effect of IL-MPEG1000 on PLA. From SEM, IL-MPEG1000 showed obvious toughening effect on PLA. Howew er, the results of TG showed that the addition of IL-MPEG1000 decreased the then-hal stability of PLA.